Questions have arisen in recent days about whether Donald Trump, his supporters, and his opponents have acted in ways that either violate the First Amendment or can be punished consistent with the First Amendment. Here are some questions and answers:
Question: Can Donald Trump, consistent with the First Amendment, exclude those who oppose his candidacy from his political rallies? Answer: Yes. Donald Trump is a private citizen. The First Amendment, like all provisions of the Constitution, restricts only the actions of government. Thus, just as a private person can constitutionally host a party that includes only his friends, Donald Trump can constitutionally hold a rally that includes only his supporters.
Question: Can Donald Trump, consistent with the First Amendment, order the removal of those who oppose his candidacy from his political rallies? Answer: Yes. Just as a private person can constitutionally call the police to remove from his party those who were not invited, Donald Trump can constitutionally call the police to remove from his political rallies those who oppose his candidacy. (Of course, if he does so he must pay the political price for his action.)
Question: Do opponents of Trump's candidacy who attend a Trump rally in defiance of an announcement that attendance is limited only to Trump supporters have a First Amendment right to attend the event because they are engaging in a "political protest"? Answer: No. The right to protest does not include the right to trespass. As a general rule, individuals do not have a First Amendment right to violate laws having nothing to do with speech -- even if they violate the law in order to engage in expressive conduct. For example, there is no First Amendment right to speed in order to get to a rally on time. There is no First Amendment right to steal a megaphone in order to speak more effectively. There is no First Amendment right to punch a policeman in order to protest police abuse. And there is no First Amendment right to trespass in order to engage in a protest.
Question: Can Donald Trump, consistent with the First Amendment, order the removal of those who oppose his candidacy from his political rallies if he does not announce in advance that they are open only to his supporters? Answer: This is tricky. It does not turn on the First Amendment, but on the law of trespass. Suppose X puts up signs inviting people to come to a neighborhood party that he's hosting in his backyard. The signs say "All Invited." They say nothing about children. When people show up with their children, X orders them to leave, saying that he never meant for children to attend. The people with children refuse to leave, explaining that they changed their plans in order to attend the party and that it is unfair for X now to order them to leave when he did not give notice of this restriction from the outset. X calls the police. Can the police arrest for trespass the people with children who refuse to leave the party in light of the fact that the invitation to the party said nothing about excluding children? I honestly don't know the answer to this question, but it seems clear that if Donald Trump wants to exclude those who don't support his candidacy from his rallies he should make that clear from the outset.
Question: Suppose Donald Trump does not announce that people who oppose his candidacy may not attend his rallies, people who oppose his candidacy attend his rallies, and Trump's supporters, seeing that Trump's opponents are carrying anti-Trump signs, tear up their signs and physically assault them. Can the Trump supporters be arrested for destruction of private property (the signs) and assault? Answer: Yes. In such circumstances, the Trump supporters have no legal right to act in this manner. They are clearly violating the law.
Question: Suppose Donald Trump does not announce that people who oppose his candidacy may not attend his rallies, people who oppose his candidacy attend his rallies, and while there they make excessive noise and otherwise engage in behavior that is intended to disrupt the event. Can they legally be removed from the event and punished for their disruptive behavior? Answer: Yes. The First Amendment does not give individuals a right to disrupt the freedom of other individuals to hold peaceful political events.
Question: Suppose Donald Trump announces that only those who support his candidacy are invited to attend his rallies, do those who oppose Trump's candidacy have a First Amendment right to protest outside the venue? Answer: Yes. This is at the very core of the First Amendment, which relies upon counter-speech to contest the ideas, opinions, and candidates we oppose. Such a protest must be undertaken in conformity with reasonable time, place, and manner regulations, but short of that the government has a constitutional obligation to permit such counter-speech.
Question: Can Donald Trump constitutionally be convicted for inciting violence? Answer: No. Although Donald Trump has made statements that both encourage and endorse violence against those who have protested his candidacy, his speech in this regard is protected by the First Amendment. Over the course of half-a-century, the Supreme Court grappled with the question of when a speaker can be punished for speech that might encourage others to engage in unlawful behavior. Initially, the Court held that speech that had even a "tendency" to cause others to commit crimes could be punished. Under that now-repudiated standard, Donald Trump could have been punished. But inspired by dissenting opinions by Justices Oliver Wendell Holmes and Louis Brandeis, who recognized the danger in allowing the government to punish individuals for speech that might cause others to commit crimes, the Court eventually came to the view that an individual can be punished for such speech only if he expressly incites unlawful conduct, only if that conduct is likely to occur imminently, and only if the harm caused by the unlawful conduct is very serious. The Court concluded that, except in those very rare circumstances, the government cannot constitutionally punish the speaker, but must focus its energies on punishing those who actually commit crimes. This standard has, over the years, protected a wide range of dissenters and dissidents and is essential to our contemporary understanding of the First Amendment. Under this standard, nothing Donald Trump has uttered has created a clear and present danger of criminal conduct of sufficient magnitude to merit criminal prosecution.
Question: Should Donald Trump be condemned for his remarks that encourage and endorse the use of violence against those who oppose him? Answer: Absolutely. The First Amendment often protects speech that is hateful, reprehensible, and odious. The fact that speech is protected by the First Amendment does not in any way mean that it is admirable, rational, or defensible. The proper response to such speech is condemnation.